桫椤科植物营养利用

Abstract Cyathea corcovadensis and Cyathea phalerata are tree ferns native to Brazil, endangered in the state of Rio Grande do Sul. Spore germination and gametophyte development in media with different nutrient formulations and activated charcoal were evaluated, aiming to develop a process for obtaining plants of the two species. Spores were sown in four semi-solid culture media: Meyer, Dyer, MS with 50% and MS with 25% of the original macronutrient concentration. For each medium, 10 replicates were carried out (flasks with 5 mg of spores/30 mL of medium), with and without 1% activated charcoal, respectively. Spore germination and gametophytic development (laminar and cordate stages) were quantified at 30, 60 and 90 days of culture. Cyathea corcovadensis and C. phalerata germinated and developed gametophytes in all media. For both species, the highest percentages of germination and cordate gametophytes (more advanced development stage) were recorded in Meyer medium without activated charcoal, which has higher concentrations of macronutrients and no micronutrients compared to the other evaluated media. We recommend cultivating the plants in Meyer medium for greater gametophytic development and subsequent sporophyte obtention, as a biotechnological tool for C. corcovadensis and C. phalerata conservation and for environmental restoration and enrichment using these tree ferns.

Knowing how species and communities respond to environmental change is fundamental in the context of climate change. The search for patterns of abundance and phenotypic variation along altitudinal gradients can provide evidence on adaptive limits. We evaluated the species abundance and the variation in morphometric and stomatal characters in five tree ferns species (Cyathea fulva, C. divergens, C. myosuroides, Alsophila firma and Gymnosphaera salvinii) distributed along an elevation gradient in a well-preserved Mexican cloud forest. Variation at the community and species level was assessed using exploratory and multivariate data analysis methods. We wanted to explore if the species abundance is environmentally determined, to determine the degree of variation along the elevation gradient, to test for differences between zones and associations with elevation, humidity and soil nutrients, and to assess contribution of the intra- and interspecific variation to the community response to elevation and soil nutrients. The studied fern community showed strong species turnover along the elevation gradient, with some influence of soil nutrient concentration, supporting environmental determinism. All measured characters displayed variation along the gradient. Stomatal characters (size and density) had significantly less variation than morphometric characters (trunk diameter, stipe length and blade length), but stomatal density also shows interesting intraspecific patterns. In general, patterns within the fern community suggest a strong influence of species identity, especially of species inhabiting the lower edge of the cloud forest, which showed the clearest morphometric and stomatal patterns, associated to contrasting environments rather than to changes in elevation. The coincidence between morphometric and stomatal patterns in this area suggest hydraulic adjustments in response to contrasting environments. Our results provide evidence that tree ferns species respond to environmental changes through adjustments of morphometric plasticity and stomatal density, which is relevant to predict possible responses to variation in environmental conditions resulting from climate change.

The purpose of this study was to present a chemical analysis of the metabolome of cell aggregates of the tree fern Cyathea smithii (J.D. Hooker) cell suspension culture. The LC/MS and GC/MS techniques were used for identification of metabolites. The kinetics of fresh weight, dry weight, and ash content showed 3.5-fold increases during 15-day-long culture. The analysis demonstrated high metabolic activity of cultured cells. In total, 160 metabolites from primary and secondary metabolism and almost 2000 compounds of unknown identity were identified. Three flavonoids—the chalcone isookanin [(2S)-2-(3,4-dihydroxyphenyl)-7,8-dihydroxy-2,3-dihydrochromen-4-one], a methoxy derivative of the flavone gardenin B (5-Hydroxy-2-(4-methoxyphenyl)-6,7,8-trimethoxy-4H-1-benzopyran-4-one), and the isoflavone tectoridin (4′,5-Dihydro-6-methoxy-7-(O-glucoside)isoflavone)—had not been previously detected in the cell culture of C. smithii. Principal component analysis revealed five distinct groups of samples; groups 4 and 5 showed the greatest similarity and corresponded to cultures on days 12 and 15, respectively. The number of differentiating compounds was 75, indicated by a heatmap showing positive and negative correlations between the days of culture. The studies described in this paper are crucial for further identification of metabolites and establishing the relationship between the metabolic composition of tree fern cells in culture and their biological activity, assessed by physiological parameters. By determining the relationship between the chemical composition of cells and their growth from culture initiation to senescence, we will provide a more complete picture of the potential for environmental factors to regulate this relationship. Based on previous studies, environmental stimuli such as electromagnetic fields or light of different wavelengths can result in altered growth physiology and cell mass, as well as metabolite diversification and accumulation. The research results presented in this paper provide a foundation for further studies aimed at predicting and regulating the productivity of C. smithii cells in suspension culture and elucidating the significance of tree fern-derived metabolic products in human cell biology, particularly in thyroid cells.

… ferns on the growth and nutrient content of four native angiosperm … leaf nutrient responses showed some evidence of nutrient … RMTryon (Cyatheaceae) is a pervasive threat to Hawaiian …

… While there is a lot we do not know about Ca uptake and … foliar Ca in ferns and how ferns influence nutrient cycling is … species in our dataset (Cibotium tree ferns) which had very high Ca:…

… non-polypod ferns across the range of soil properties in Hawaii; tree ferns generally become … gleichenioid ferns are common in patches, particularly on slopes, at all but the nutrient-rich …

… Specifically, we aimed to assess whether mycorrhization provided ecological advantages relative to nutrient uptake. If this was the case, we would expect the following relationships: …

… where plant available sources of mineral nutrients and N are patchily distributed. Many … to nutrient uptake remain to be discovered among plant species restricted to highly nutrient-…

Abstract Terrestrial and epiphytic herbaceous forest species have different ecological qualities and leaf stoichiometry. Ferns represent a great component of herbaceous forest species in tropical regions with different lifeforms and evolutionary histories. However, little is known about the differences in leaf stoichiometry between the lifeforms. We studied the concentrations of leaf elements (N, P, K, Ca and Mg) between lifeforms (16 terrestrial, 4 epiphytic) and evolutionary clades (12 polypods, 8 non-polypods). The leaves were collected from the field, acid-digested and analyzed for nutrient elements. Results show that epiphytic species had a higher concentration of most leaf elements. Epiphytes had a lower N:P ratio compared with terrestrial ones. This suggests that epiphytes were nutrient-limited, relying on stochastic elements supply compared to terrestrial species which have a constant supply. Epiphytes tend to accumulate higher element concentration beyond their immediate metabolic needs, defined as luxury consumption. Epiphytes showed a higher concentration of P and Ca for their necessity of coping with severe habitat conditions and sclerophyll leaves. We found that modern polypod and archaic non-polypod ferns are significant stoichiometry different for K. The results contribute to the context of the poorly studied stoichiometry of tropical Asian fern species and their ecophysiology.

… nor excessive, we conclude that our studied ferns were not exposed to nutritional Mn problems. … of Cyatheaceae, Dipteridaceae, Gleicheniaceae, and Marattiaceae, with the latter thre…

… pH and a substrate that is rich in mineral nutrition, but that growth was … Distribution of tree ferns (Cyatheaceae) across the … fern Cyathea caracasana (Cyatheaceae) across a sucessional …

… differences were the Hymenophyllaceae (filmy ferns) and Cyatheaceae (scaly tree ferns). The … Among the Cyatheaceae, two species differed in the NþP-treated plots in Cajanuma – …

Forest community assembly is usually framed in terms of sporophyte dynamics; however, the recruitment and maintenance of fern populations, frequently influential in forest composition and structure, are initially determined by gametophytes. Sporophytes of three Cyathea tree fern species show habitat partitioning along gradients of phosphorus and light; we asked whether gametophyte niche differences parallel this pattern. To compare niche characteristics among taxa we compared growth rates to a size threshold (≥3 mm) of gametophytes under controlled conditions using a multi-factorial, multi-level (3 × 4) experiment, varying irradiance (5.4 ± 4.4; 59.1 ± 44.3; 107 ± 74.1 µmol m−2 s−1) and orthophosphate concentrations (5, 10, 20, 40 mg kg−1). Gametophytes of the pioneer species C. medullaris developed to the size threshold across a broad range of phosphate and irradiance treatments (more than 20% of gametophytes in ≥ 7 of the 12 treatments), peaking at 20 mg kg−1 P and 60 µmol m−2 s−1 irradiance. The growth rates of the forest understorey species C. dealbata and C. smithii also peaked at 60 µmol m−2 s−1 but varied across treatments, suggesting niche differentiation along irradiance and orthophosphate gradients. Our analysis suggests that gametophyte development is strategically aligned to the ecological habits of sporophytes and that forest community assembly is likely strongly influenced by the independent gametophyte life-stage.

… (Cyatheaceae) a pioneer tree fern. I compared leaf litter … influence organic matter dynamics and nutrient cycling rates in … The differing decomposition rates and nutrient dynamics of …

… nitrogen use efficiency of the invasive tree fern was significantly higher than that of the native tree ferns, … The fronds of the invasive tree fern species had a significantly shorter life span …

The plant economics spectrum describes the trade-off between plant resource acquisition and storage, and sheds light on plant responses to environmental changes. However, the data used to construct the plant economics spectrum comes mainly from seed plants, thereby neglecting vascular non-seed plant lineages such as the ferns. To address this omission, we evaluated whether a fern economics spectrum exists using leaf and root traits of 23 fern species living under three subtropical forest conditions differing in light intensity and nutrient gradients. The fern leaf and root traits were found to be highly correlated and formed a plant economics spectrum. Specific leaf mass and root tissue density were found to be on one side of the spectrum (conservative strategy), whereas photosynthesis rate, specific root area, and specific root length were on the other side of the spectrum (acquisitive strategy). Ferns had higher photosynthesis and respiration rates, and photosynthetic nitrogen-use efficiency under high light conditions and higher specific root area and lower root tissue density in high nutrient environments. However, environmental changes did not significantly affect their resource acquisition strategies. Thus, the plant economics spectrum can be broadened to include ferns, which expands its phylogenetic and ecological implications and utility. This article is protected by copyright. All rights reserved.

… In another study, three tree fern … nutrient-use efficiencies, and shorter LLS and PBT, ferns in disturbed forests exhibit a distinct quicker return energy-use strategy as compared with ferns …

… , instantaneous water use efficiency, leaf nitrogen content and … Important findings (1) Leaf dry matter content of the three fern … to understorey filtering by tree ferns. Journal of Vegetation …

… ferns in a similar way to angiosperms and highlight the association of the early tree fern … offs or “economic spectra” that reflect resource use efficiency strategies of species. One spectrum …

PREMISE Plant ecological strategies are often defined by the integration of underlying traits related to resource acquisition, allocation, and growth. Correlations between key traits across diverse plants suggest that variation in plant ecological strategies is largely driven by a fast-slow continuum of plant economics. However, trait correlations may not be constant through the life of a leaf and it is still poorly understood how trait function varies over time in long-lived leaves. METHODS Here, we compared trait correlations related to resource acquisition and allocation across three different mature frond age cohorts in a tropical fern species, Saccaloma inaequale. KEY RESULTS We found that fronds exhibited high initial investments of nitrogen and carbon, but with declining return in photosynthetic capacity after the first year. In the youngest fronds, we found water-use efficiency to be significantly lower than the oldest mature fronds, due to increased transpiration rates. Our data suggest that middle-aged fronds are more efficient relative to younger, less water-use efficient fronds, and that older fronds exhibit greater nitrogen investments without higher photosynthetic return. In addition, several trait correlations expected under the Leaf Economics Spectrum (LES), do not hold within this species and some trait correlations only appear in fronds of a specific developmental age. CONCLUSIONS These findings contextualize the relationship between traits and leaf developmental age with those predicted to underlie plant ecological strategy and the LES, and is among the first pieces of evidence for when relative physiological trait efficiency is maximized in a tropical fern species. This article is protected by copyright. All rights reserved.

… In the fern, daily carhon haiance … -term nitrogen-use efficiency of all three species (Table 4). This suggests that it is possible to estimate annual leaf carbon gain from leaf N content using …

Fern species are an important component of the diversity of forest plant communities, but very little is known about how fern communities assemble in different environments. In this study, we use multiple trait-based tests to examine the relationships between several key eco-physiological traits which are direct indicators of shade and drought tolerance, and the abundance of fern species in pine forest (PF), pine and mixed broad leaf forest (PMBF) and matured broad leaf forest (MBF) in southern China. These forests are characterized by decreasing light but increasing water availability during succession, and the fern communities correspondingly differ in species composition. We tested community assembly using functional trait distributions and found that habitat filtering and exclusion of weak competitive traits among coexisting species jointly explain fern shade tolerance as measured by photosynthetic capacity (PR), photosynthetic nutrient efficiency (PNUE and PPUE) and water use efficiency as measured by carbon isotope ratio (CIR), and constitute important determinants of fern community assembly in all three forests. These observed fern plant strategies are consistent with known responses of other plant taxa such as flowering plants in similar successional environments and illustrate the value of functional trait based analyses to study community assembly.

Montane cloud forests are among the most threatened ecosystems globally. These forests face several stressors, such as deforestation and climate change, jeopardizing their functional sustainability. Although microbial communities act as key regulators of the soil nutrient cycles, microfungal and bacterial diversity remains largely unknown in this ecosystem. We evaluated cultivable soil microbial diversity associated with the soil below iconic plant taxa (Cyatheaceae and Juglandaceae) in a pristine montane cloud forest of Mexico, and explored small-scale ecological patterns linked to edaphic biogeochemical variables. Our findings revealed the copious occurrence of entomopathogenic fungi such as Tolypocladium geodes and potentially phosphate solubilizer bacteria such as Pseudomonas and Bacillus spp. We observed a strong association between edaphic microbial assemblages and environmental variables such as soil C:N:P availability. This close relationship with the physical setting should be considered for the development of management and in situ conservation strategies aiming to preserve microbial functions.

The purpose of this study was to investigate the aluminum (Al) concentration in Lycopodium clavatum, Dicranopteris flexuosa, Sticherus nudus, Anemia villosa, Cyathea gibbosa, …

The diversity of plant-associated microbial communities is shaped by both host factors and the environment. Natural environmental gradients, specifically elevational ones, can serve as study systems to understand community and ecosystem responses to environmental changes, however the relationship between elevation and microbial diversity is not completely understood, especially in non-model systems such as wild plants. In this paper we explored the role of environmental factors in shaping the diversity and structure of the rhizosphere and phyllosphere of the cloud forest tree fern Cyathea fulva. Samples of phyllosphere, rhizosphere and soil were collected from 15 individual tree ferns across five forest plots along an elevation gradient ranging from 1978 to 2210 meters above sea level. Physicochemical soil data were collected, along with environmental data of all plots. Using 16S rRNA and ITS1 amplicon sequencing, we tested for differences in diversity and composition of bacterial and fungal communities and their potential abiotic drivers. We found that bacterial alpha diversity decreased with elevation in the phyllosphere and rhizosphere, but for fungi this pattern was only found in the rhizosphere. We also observed significant changes in community structure and composition with elevation in both the fungal and bacterial phyllosphere and rhizosphere. Our results suggest a close relationship between elevation and the overall microbial structure associated with tree ferns. We envision this information will help to further understand the dynamics between microbiota and wild plants, contributing to the conservation of necessary interactions for plants and ecosystems wellbeing.

… Because the tiny gametophytes exhibit simple rhizoid structures instead of root systems, AM fungal associations may play an important role in water and nutrient uptake in pteridophyte …

Abstract Ferns are known to have a lower incidence of mycorrhization than angiosperms. It has been suggested that this results from carbon being more limiting to fern growth than nutrient availability, but this assertion has not been tested yet. In the present study, we took advantage of a fertilization experiment with nitrogen and phosphorus on cloud forest plots of the Ecuadorean Andes for 15 years. A previous analysis revealed changes in the abundances of fern species in the fertilized plots compared to the control plots and hypothesized that this might be related to the responses of the mycorrhizal relationships to nutrient availability. We revisited the plots to assess the root‐associated fungal communities of two epiphytic and two terrestrial fern species that showed shifts in abundance. We sampled and analyzed the roots of 125 individuals following a metabarcoding approach. We recovered 1382 fungal ASVs, with a dominance of members of Tremellales (Basidiomycota) and Heliotales (Ascomycota). The fungal diversity was highly partitioned with little overlap between individuals. We found marked differences between terrestrial and epiphytic species, with the latter fundamentally missing arbuscular mycorrhizal fungi (AMF). We found no effect of fertilization on the diversity or relative abundance of the fungal assemblages. Still, we observed a direct impact of phosphorus fertilization on its concentration in the fern leaves. We conclude that fern–fungi relationships in the study site are not restricted by nutrient availability and suggest the existence of little specificity on the fungal partners relative to the host fern species.

… It may also help us with the identification of genes implicated in nutrient uptake in ferns. … occur in Cyatheaceae. Pioneer species could be exposed to high levels of Al in acidic soils, …

… Effects of the nutrient stoichiometry of carbon, nitrogen, and phosphorus were studied on sex … The tallest fern in the world is the tree fern Cyathea australis, which grows to a height of 20 …

SynopsisThis assessment of selected literature on pteridophyte edaphic adaptation is presented in three parts: (1) pH and general soil nutrient background, (2) growth responses to specific inorganic ions and frond mineral content, and (3) collected works onPteridium aquilinumedaphic adaptations. In this report, a case is made for the overriding effect of both soil pH and inorganic ion content in determining pteridophyte occurrence. Recommendations are made for more field and laboratory co-ordinated studies, especially as they pertain to the determination of species-specific amplitudes of adaptation, and for the initiation of physiological and metabolic investigations into the basis of these edaphic adaptations.

Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have focused on the physiological capacity and stress tolerance of both the sporophyte and the gametophyte generations. In this review, we examine these insights through the lens of plant water relations, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and variously sized megaphylls are shared between ferns and more derived lineages, and offer an opportunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gametophyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic.

Publisher Summary This chapter discusses the fundamental aspects of the edaphic adaptations of Ancient Living Vascular Plants (ALVP) such as clubmosses, horsetails, ferns, and …

The rhizosphere is considered a highly complex and dynamic ecosystem. Rhizosphere soil microorganisms influence the growth and development of plants by mediating the transformation and absorption of nutrients. In order to explore the microbial community composition and diversity of Alsophila spinulosa growing in different habitats. Rhizosphere samples were collected from four different habitats within the Chishui Alsophila National Nature Reserve in Guizhou Province, China. According to the high-throughput sequencing results of 16 s rDNA and ITS, Proteobacteria and Ascomycota were the most abundant bacterial and fungal phyla in the rhizosphere soil of all four habitats. The alpha diversity analysis indicated that two particular habitats, Buddha Rock and Botanical Garden, harbored the highest microbial richness and diversity. LEfSe analysis revealed that Buddha Rock contained the highest relative abundance of Bacteroidetes compared to the other three study areas. Meanwhile, Tiantang Gou contained the highest relative abundance of Basidiomycota. Bacterial community composition and diversity were greatly influenced by soil pH, while fungal community composition and diversity were greatly influenced by available phosphorus, organic carbon, sucrase, and urease. The results of this study provide a scientific basis for the habitat restoration of A. spinulosa, and the improvement of the structure of the A. spinulosa rhizosphere soil microbial community. Laying a theoretical foundation for the next screening of inter-root functional flora.

Introduction The “rhizosphere effect” in plants occurs within approximately 5 mm from the root surface, where microbial communities exhibit distinct species composition and structural characteristics compared to non-rhizospheric soil. Root-associated fungi play crucial roles in nutrient acquisition enhancement, stress resistance improvement, organic matter decomposition, and carbon cycle promotion. Current research shows limited understanding of the rhizospheric fungal communities in Alsophila spinulosa, a rare and endangered plant species. Methods This study conducted a comparative analysis of fungal community composition and structural differences between A. spinulosa rhizospheric and non-rhizospheric soils. The functional roles of fungi in these distinct communities were systematically analyzed, with particular emphasis on identifying keystone fungal taxa within the rhizosphere, and explained the construction process of fungal communities. Results The results showed that there was no difference in α diversity between the rhizosphere and non-rhizosphere soil fungal communities of A. spinulosa, but the β diversity was significantly differentiated, indicating that the difference between rhizosphere and non-rhizosphere fungal communities was mainly reflected in species composition rather than species number. The two communities have common dominant phylum: Ascomycetes and Basidiomycetes, and common dominant genera: Mortierella and Saitozyma. The functional type was mainly saprotic. Linear discriminant analysis effect size (LEfSe) analysis revealed four biomarker genera (Arthopyrenia, Hypochnicium, Tremella, and Syncephalis) enriched in the A. spinulosa rhizospheric fungal community. Venn diagram analysis identified 169 core genera within this community, with Flavodon exclusively present in the rhizosphere. Mechanistic analysis of community assembly demonstrated that stochastic processes predominantly governed the structuring of rhizospheric fungal communities. Discussion In conclusion, this study elucidates the functional composition and assembly mechanisms of rhizospheric fungal communities in A. spinulosa, while identifying keystone fungal taxa potentially critical to its survival. Future investigations should: Quantify the specific contribution of Flavodon to A. spinulosa; Decipher the mechanistic linkages between these fungi and the plant’s stress resistance traits; Implement plant–soil-microbe synergistic restoration strategies to enhance natural regeneration capacity of A. spinulosa populations.

Tree ferns hold significant ecological and socioeconomic value. In Nepal, they have restricted distribution, occurring in a few patches from eastern to central Nepal. In the localities …

… in similar forest ecosystems where decomposition and nutrient cycling are central[67]. The … decomposition and nutrient cycling, which may underpin the nutrient retrieval strategy of A.…

Alsophila spinulosa is a tree fern designated as a second-class nationally protected species in China and valued for its medicinal and ornamental properties. Its slow growth and susceptibility to environmental stresses pose challenges to its cultivation. Plant-growth-promoting rhizobacteria (PGPR) can enhance plant development by producing phytohormones, such as indole-3-acetic acid (IAA). In this study, 39 IAA-producing strains were isolated from the rhizosphere of A. spinulosa. Morphological and molecular analyses identified the highest IAA-producing strain, R74, as Burkholderia pyrrocinia. Its optimal inoculum age was determined to be 12–20 h, and its optimal culture conditions for IAA production were 24 h of incubation, 32 °C and pH 7.0. Whole-genome sequencing revealed that the genome of strain R74 is 8,347,169 bp in size with a GC content of 67%, comprising 7543 genetic elements. Further genomic analysis showed that IAA biosynthesis in R74 involves the tryptophan side-chain oxidase (TSO) pathway and the tryptophan-independent pathway. Pot experiments revealed that inoculation with R74 increased the height, root length, stem diameter, and biomass of A. spinulosa seedlings. It also increased antioxidant enzyme activities, elevated soluble protein and chlorophyll contents, and reduced malondialdehyde levels. This study provides an empirical basis for the development of Burkholderia-based biofertilizers to promote A. spinulosa growth.

… Alsophila firma is a deciduous tree fern considered as an … (AMF) within the roots of the Alsophila firma in rainy and dry season. … 3), therefore storage of nutrients in the trunk of A. firma (…

The uncontrolled invasion of moso bamboo (Phyllostachys pubescens) dramatically alters soil nitrogen cycling and destroys the natural habitat of Alsophila spinulosa. Nevertheless, no clear evidence points out the role of denitrifying bacteria in the invasion of bamboo into the habitat of A. spinulosa. In the present study, we found that low (importance value 0.0008), moderate (0.6551), and high (0.9326) bamboo invasions dramatically altered the underground root biomass of both P. pubescens and A. spinulosa. The root biomass of A. spinulosa was maximal at moderate invasion, indicating that intermediate disturbance might contribute to the growth and survival of the colonized plant. Successful bamboo invasion significantly increased rhizospheric soil available nitrogen content of A. spinulosa, coupled with elevated denitrifying bacterial abundance and diversity. Shewanella, Chitinophaga, and Achromobacter were the primary genera in the three invasions, whereas high bamboo invasion harbored more denitrifying bacteria and higher abundance than moderate and low invasions. Further correlation analysis found that most soil denitrifying bacteria were positively correlated with soil organic matter and available nitrogen but negatively correlated with pH and water content. In addition, our findings illustrated that two denitrifying bacteria, Chitinophaga and Sorangium, might be essential indicators for evaluating the effects of bamboo invasion on the growth of A. spinulosa. Collectively, this study found that moso bamboo invasion could change the nitrogen cycling of colonized habitats through alterations of denitrifying bacteria and provided valuable perspectives for profound recognizing the invasive impacts and mechanisms of bamboo expansion.

Although the effects of N deposition on forest plants have been widely reported, few studies have focused on rare and endangered fern species (REFs). Information is also lacking on the effects of micro-environments on REFs. We investigated the effects of N addition (canopy and understory N addition, CAN, and UAN) and micro-environments (soil and canopy conditions) on the functional traits (growth, defense, and reproduction; 19 traits in total) of two REFs—Alsophila podophylla and Cibotium baromet—in a subtropical forest in South China. We found that, compared to controls, CAN or UAN decreased the growth traits (e.g., plant height, H) of C. baromet, increased its defense traits (e.g., leaf organic acid concentrations, OA), delayed its reproductive event (all-spore release date), and prolonged its reproductive duration. In contrast, A. podophylla showed increased growth traits (e.g., H), decreased defense traits (e.g., OA), and advanced reproductive events (e.g., the all-spore emergence date) under CAN or UAN. Meanwhile, the negative effects on the C. baromet growth traits and A. podophylla defense traits were stronger for CAN than for UAN. In addition, the soil chemical properties always explained more of the variations in the growth and reproductive traits of the two REFs than the N addition. Our study indicates that, under simulated N deposition, C. baromet increases its investment in defense, whereas A. podophylla increases its investment in growth and reproduction; this may cause an increasing A. podophylla population and decreasing C. baromet population in subtropical forests. Our study also highlights the importance of considering micro-environments and the N-addition approach when predicting N deposition impact on subtropical forest REFs.

… decomposition and nutrient cycling rates, our results suggest that some invasive ferns, such as Sphaeropteris, could also stimulate increased nutrient turnover. Sphaeropteris produces …

… The Australian tree fern Sphaeropteris cooperi is an invasive … Sphaeropteris cooperi had a significantly higher growth rate, … Leaf construction cost, nutrient concentration, and net CO2 …